| Coverage Policy Manual | |
| Policy #: | 2018000 |
| Category: | Medicine |
| Initiated: | September 2018 |
| Last Review: | June 2024 |
|
|
|
|||||||||||
| Leadless Cardiac Pacemakers | |
|
|
|
| Description: |
Pacemakers are intended to be used as a substitute for the heart’s intrinsic pacing system to correct cardiac rhythm disorders. By providing an appropriate heart rate and heart rate response, cardiac pacemakers can reestablish effective circulation and more normal hemodynamics that are compromised by a slow heart rate. Pacemakers vary in system complexity and can have multiple functions as a result of the ability to sense and/or stimulate both the atria and the ventricles.
Transvenous pacemakers or pacemakers with leads (hereinafter referred as conventional pacemakers) consist of 2 components: a pulse generator (also referred to as battery component) and electrodes (also referred to as leads). The pulse generator consists of a power supply and electronics that can provide periodic electrical pulses to stimulate the heart. The generator is commonly implanted in the infraclavicular region of the anterior chest wall and placed in a pre-pectoral position, but in some cases a sub-pectoral position is advantageous. The unit generates the electrical impulse which is transmitted to the myocardium via the electrodes affixed to the myocardium to sense and pace the heart as needed.
Conventional pacemakers are also referred to as single-chamber or dual-chamber systems. In single-chamber systems, only 1 lead is placed, typically in the right ventricle. In dual-chamber pacemakers, 2 leads are placed-one in the right atrium and the other in right ventricle. Single-chamber ventricular pacemakers are much more commonly used in practice.
Annually, approximately 200,000 pacemakers are implanted in the United States and 1 million worldwide (Reddy, 2015). Implantable pacemakers are considered life-sustaining, life-supporting class III devices for patients with a variety of bradyarrhythmias. Pacemaker systems have matured over the years with well-established, acceptable performance. As per the Food and Drug Administration (FDA), the early performance of conventional pacemaker systems from implant through 60 to 90 days has usually demonstrated acceptable pacing capture thresholds and sensing. Intermediate performance from 90 days through more than 5 years has usually demonstrated reliability of the pulse generator and lead technology. Chronic performance from 5 to 10 years includes a predictable decline in battery life and mechanical reliability but a vast majority of patients receive excellent pacing and sensing free of operative or mechanical reliability failures.
Even though the safety profile of conventional pacemakers is excellent, they are associated with complications particularly related to leads. Most safety data on the use of conventional pacemakers come from registries from Europe, particularly from Denmark where all pacemaker implants are recorded in a national registry. These data are summarized below. It is important to recognize that valid comparison of complication rates is limited by differences in definitions of complications, which results in a wide variance of outcomes, as well as by the large variance in follow-up times, use of single-chamber or dual-chamber systems, and data reported over more than 2 decades (Udo, 2012). As such, the following data are contemporary and limited to single-chamber systems when reported separately.
In many cases when a conventional pectoral approach is not possible, alternative approaches such as epicardial pacemaker implantation and trans-iliac approaches have been used (Haight, 2018). Cohen et al reported outcomes from a retrospective analysis of 123 patients who underwent 207 epicardial lead implantations (Cohen, 2001). Congenital heart disease was present in 103 (84%) of the patients. Epicardial leads were followed for 29 months (range, 1 to 207 months). Lead failure was defined as the need for replacement or abandonment due to pacing or sensing problems, lead fracture, or phrenic/muscle stimulation. The 1-, 2-, and 5-year lead survival was 96%, 90%, and 74%, respectively. Epicardial lead survival in those placed by a subxiphoid approach was 100% at 1 year and at 10 years, by the sternotomy approach (93.9% at 1 year and 75.9% at 10 years) and lateral thoracotomy approach (94.1% at 1 year and 62.4% at 10 years).
Doll et al reported results of a randomized controlled trial comparing epicardial implantation versus conventional pacemaker implantation in 80 patients with indications for cardiac resynchronization therapy (Doll, 2008). The authors reported that the conventional pacemaker group had a significantly shorter intensive care unit stay, less blood loss, and shorter ventilation times while the epicardial group had less exposure to radiation and less use of contrast medium. The left ventricular pacing threshold was similar in the 2 groups at discharge but longer in the epicardial group during follow-up. Adverse events were also similar in the 2 groups. The following events were experienced by 1 (3%) patient each in the epicardial group: pleural puncture, pneumothorax, wound infection, acute respiratory distress syndrome, and hospital mortality.
As a less invasive alternative to the epicardial approach, the trans-iliac approach has also been utilized. Data using trans-iliac approach is limited. Multiple other studies with smaller sample size report a wide range of lead longevity.
Harake et al reported a retrospective analysis of 5 patients who underwent a transvenous iliac approach (median age, 26.9 years) (Harake, 2018). Pacing indications included AV block in 3 patients and sinus node dysfunction in 2 patients. After a median follow-up of 4.1 years (range, 1.0 to 16.7 years), outcomes were reported for 4 patients. One patient underwent device revision for lead position-related groin discomfort; a second patient developed atrial lead failure following a Maze operation and underwent lead replacement by the iliac approach. One patient underwent heart transplantation 6 months after implant with only partial resolution of pacing-induced cardiomyopathy. Tsutsumi et al reported a case series of 4 patients from Japan in whom conventional pectoral approach was precluded due to recurrent lead infections (n=1), superior vena cava obstruction following cardiac surgery (n=2) and a postoperative dermal scar (n=1). The mean follow-up was 24 months and the authors concluded the iliac vein approach was satisfactory and less invasive alternative to epicardial lead implantation. However, the authors reported that the incidence of atrial lead dislodgement using this approach in the literature ranged from 7% to 21%. Experts who provided clinical input reported that trans-iliac or surgical epicardial approach requires special expertise and long-term performance is suboptimal (Tsutsumi, 2010).
Reported Complication Rates with Conventional Pacemakers (Heale, 2006; Kirkfeldt, 2011; FDA, 2016)
The potential advantages of leadless pacemakers fall into 3 categories: avoidance of risks associated with intravascular leads in conventional pacemakers, avoidance of risks associated with pocket creation for placement of conventional pacemakers, and an additional option for patients who require a single chamber pacer (AHA, 2016).
Lead complications include lead failure, lead fracture, insulation defect, pneumothorax, infections requiring lead extractions/replacements that can results in a torn subclavian vein or tricuspid valve. In addition, there are potential risk of venous thrombosis and occlusion of the subclavian system from the leads. Use of a leadless system eliminates such potential risks with the added advantage that patient has vascular access preserved for other medical conditions (e.g., dialysis or chemotherapy).
Pocket complications include infections, erosions and pain that can be eliminated with leadless pacemakers. Further, a leadless cardiac pacemaker may be more comfortable and appealing as unlike conventional pacemakers, patients are unable to see or feel or have implant scar on the chest wall with leadless pacemakers.
Lastly, leadless pacemakers may also be a better option than a surgical endocardial pacemaker for patients with no vascular access due to renal failure or congenital heart disease.
The Micra AV device supports maintenance of atrioventricular (AV) synchrony by sensing atrial mechanical contraction (A4 signal). Several small-cohort studies have investigated the relationship between parameters (e.g., clinical and echocardiographic) and A4 signal amplitude. Briongos-Figuero et al investigated clinical and echocardiographic predictors of optimal AV synchrony, defined as 85% or more of total cardiac cycles being synchronous, in individuals with successful Micra AV implant (N=43). The authors performed univariate analyses followed by multivariate analysis. They found diabetes and chronic obstructive pulmonary disease to be associated with A4 signal amplitude, however no echocardiographic parameters were associated with A4 signal amplitude (Briongos-Figuero, 2023). Troisi et al studied the relationship between echocardiographic parameters and A4 signal amplitude in individuals implanted with Micra AV (N=21). The authors concluded echocardiographic parameters, particularly related to left atrial function, may be related to successful AV synchrony (Troisi, 2024). Kawatani et al et al studied predictors of AV synchrony in individuals with Micra AV implants (N=50). Participants were stratified into 2 groups, high and low A4 amplitude. In a multivariate analysis, maximum deflection index was the only parameter associated with low A4 amplitude (Kawatani, 2024). These studies were exploratory and results among the studies were inclusive. More research is in larger cohort studies is needed to produce more conclusive evidence on parameters that are predictive of AV synchrony.
Currently, real-world evidence of long-term battery life for leadless pacemakers is limited. Breeman et al studied the battery life of the Micra VR after implantation (N=153). The manufacturer's predicted battery life for the Micra VR is 12 years. Using mixed models to assess changes in electrical parameters over time, the authors concluded that for a majority of individuals the expected batter longevity is more than 8 years (Breeman, 2023). Due to the limited lifespan of leadless pacemakers, they are designed to be retrievable (e.g., the helix fixation design of the Aveir devices). However, evidence on the safety and success of device retrieval is limited to case reports (Ip, 2023: Ip, 2024; Ip, 2024).
Li et al studied different anatomical placements in the ventricular septum of the Micra VR (N=15) and found no impact on safety or electrical characteristics of the device (Li, 2023). In a large cohort study in individuals with Micra AV or Micra VR implants (N=358) by Shantha et al, the authors found apical septum placement was associated with a higher risk of pacing-induced cardiomyopathy compared to mid/high septum placement (Shantha, 2023). Larger randomized studies are needed to confirm how anatomical placement of the device impacts safety and effectiveness.
Leadless pacemakers are self-contained in a hermetically sealed capsule. The capsule houses a battery and electronics to operate the system. Similar to most pacing leads, the tip of the capsule includes a fixation mechanism and a monolithic controlled release device. The controlled release device elutes glucocorticosteroid to reduce acute inflammation at the implantation site. Leadless pacemakers have rate responsive functionality, and current device longevity estimates are based on bench data. Estimates have shown that these devices may last over 10 years depending on the programmed parameters (FDA, 2016).
Four systems are currently being evaluated in clinical trials: (1) the Micra Transcatheter Pacing System (Medtronic), (2) the Aveir VR Leadless Pacemaker (Abbott; formerly Nanostim, St. Jude Medical); (3) the Aveir DR Dual Chamber Leadless Pacemaker System (Abbott); and (4) the WiCS Wireless Cardiac Stimulation System (EBR Systems). The first 3devices are free-standing capsule-sized devices that are delivered via femoral venous access using a steerable delivery sheath. However, the fixing mechanism differs between the Micra and Aveir devices. In the Micra Transcatheter Pacing System, the fixation system consists of 4 self-expanding nitinol tines, which anchor into the myocardium; for the Aveir devices, there is a screw-in helix that penetrates into the myocardium. In the Micra and Aveir devices, the cathode is steroid eluting and delivers pacing current; the anode is located in a titanium case. The forth device, WiCS system differs from the other devices; this system requires implanting a pulse generator subcutaneously near the heart, which then wirelessly transmits ultrasound energy to a receiver electrode implanted in the left ventricle. The receiver electrode converts the ultrasound energy and delivers electrical stimulation to the heart sufficient to pace the left ventricle synchronously with the right (FDA, 2016).
Of these 4, only the Micra and Aveir single-chamber transcatheter pacing systems and the Aveir dual chamber transcatheter pacing system are approved by the FDA and commercially available in the U.S. Multiple clinical studies of the Aveir predecessor device, Nanostim, have been published but trials have been halted due to the migration of the docking button in the device and premature battery depletion (Reddy, 2015; Reddy, 2016; Reddy, 2014; Knopps, 2015; Lakkireddy, 2017; Sperzel, 2018). These issues have since been addressed with the Aveir device (Reddy, 2022).
The Micra is about 25.9mm in length and introduced using a 23 French catheter via the femoral vein to the right ventricle. It weighs about 1.75 grams and has an accelerometer-based rate response (Zuckerman, 2016).
The Aveir is about 42 mm in length and introduced using a 25 French catheter to the right ventricle. It also weighs about 3 grams and uses a temperature-based rate response sensor (FDA, 2022).
The atrial Aveir DR is about 32.3 mm in length and weighs about 2.1 grams. The ventricular Aveir DR is about 38.0 mm in length and weighs about 2.4 grams. Both are introduced using a 25 French catheter. The system uses a temperature-based rate response (FDA, 2023).
Regulatory Status
In April 2016, Micra® Transcatheter Pacing System (Medtronic) was approved by FDA through the premarket approval process for use in patients who have experienced 1 or more of the following conditions:
In January 2020, the Micra AV Transcatheter Pacing System Model MC1AVR1 and Application Software Model SW044 were approved as a PMA supplement (S061) to the Micra system described above. The Micra AV includes an enhanced algorithm to provide AV synchronous pacing.
In November 2021, the U.S. FDA issued a letter to health care providers regarding the risk of major complications related to cardiac perforation during implantation of leadless pacing systems (FDA, 2022). Specifically, the FDA states that "real-world use suggests that cardiac perforations associated with Micra leadless pacemakers are more likely to be associated with serious complications, such as cardiac tamponade or death, than with traditional pacemakers." This letter has been removed from the FDA website as of April 2024.
In March 2022, the Aveir VR Leadless Pacemaker was approved by the U.S. FDA through the premarket approval process (PMA number: P150035) for use in patients with bradycardia and:
Rate-Modulated Pacing is indicated for patients with chronotropic incompetence, and for those who would benefit from increased stimulation rates concurrent with physical activity.
In June 2023, a premarket approval application supplement with expanded indications to include dual-chamber pacing with the Aveir DR Leadless System was approved by the FDA (PMA number: P150035) for use in individuals with 1 or more of the following permanent conditions:
Rate-Modulated Pacing is indicated for individuals with chronotropic incompetence, and for those who would benefit from increased stimulation rates concurrent with physical activity.
Dual-Chamber Pacing is indicated for individuals exhibiting:
|
|
|
|
|
Policy/ Coverage: |
Effective October 2024
Meets Primary Coverage Criteria Or Is Covered For Contracts Without Primary Coverage Criteria
Use of the Micra single-chamber transcatheter pacing system and the Aveir single-chamber transcatheter pacing system meets member benefit certificate primary coverage criteria that there be scientific evidence of effectiveness when all of the following are met:
Does Not Meet Primary Coverage Criteria Or Is Not Covered For Contracts Without Primary Coverage Criteria
Use of the Micra single-chamber transcatheter pacing system or the Aveir single-chamber transcatheter pacing system for any indication or condition not described above does not meet member benefit certificate primary coverage criteria that there be scientific evidence of effectiveness.
For members with contracts without primary coverage criteria, use of the Micra single-chamber transcatheter pacing system or the Aveir single-chamber transcatheter pacing system for any indication or condition not described above is considered investigational. Investigational services are specific contract exclusions in most member benefit certificates of coverage.
Leadless left ventricular pacing does not meet member benefit certificate primary coverage criteria that there be scientific evidence of effectiveness.
For members with contracts without primary coverage criteria, use of leadless left ventricular pacing is considered investigational. Investigational services are specific contract exclusions in most member benefit certificates of coverage.
Leadless bi-ventricular pacing does not meet member benefit certificate primary coverage criteria that there be scientific evidence of effectiveness.
For members with contracts without primary coverage criteria, use of leadless bi-ventricular pacing is considered investigational. Investigational services are specific contract exclusions in most member benefit certificates of coverage.
The Aveir DR dual-chamber pacing system does not meet member benefit certificate primary coverage criteria that there be scientific evidence of effectiveness.
For members with contracts without primary coverage criteria, the Aveir DR dual-chamber pacing system is considered investigational. Investigational services are specific contract exclusions in most member benefit certificates of coverage.
Effective September 2023 – September 2024
Meets Primary Coverage Criteria Or Is Covered For Contracts Without Primary Coverage Criteria
Use of the Micra single-chamber transcatheter pacing system and the Aveir single-chamber transcatheter pacing system meets primary coverage criteria when all of the following are met:
Does Not Meet Primary Coverage Criteria Or Is Not Covered For Contracts Without Primary Coverage Criteria
Use of the Micra single-chamber transcatheter pacing system or the Aveir single-chamber transcatheter pacing system for any indication or condition not described above, does not meet primary coverage criteria that there be scientific evidence of effectiveness.
For contracts without primary coverage criteria, use of the Micra single-chamber transcatheter pacing system or the Aveir single-chamber transcatheter pacing system for any indication or condition not described above is considered investigational. Investigational services are specific contract exclusions in most member benefit certificates of coverage.
Leadless left ventricular pacing does not meet primary coverage criteria that there be scientific evidence of effectiveness.
For contracts without primary coverage criteria, use of leadless left ventricular pacing is considered investigational. Investigational services are specific contract exclusions in most member benefit certificates of coverage.
Leadless bi-ventricular pacing does not meet primary coverage criteria that there be scientific evidence of effectiveness.
For contracts without primary coverage criteria, use of leadless bi-ventricular pacing is considered investigational. Investigational services are specific contract exclusions in most member benefit certificates of coverage.
Effective May 2023 through August 2023
Meets Primary Coverage Criteria Or Is Covered For Contracts Without Primary Coverage Criteria
Micra single-chamber transcatheter pacing system meets primary coverage criteria when all of the following are met:
Does Not Meet Primary Coverage Criteria Or Is Not Covered For Contracts Without Primary Coverage Criteria
Use of the Micra single-chamber transcatheter pacing system for any indication or condition not described above, does not meet primary coverage criteria that there be scientific evidence of effectiveness. For contracts without primary coverage criteria, use of the Micra single-chamber transcatheter pacing system for any indication or condition not described above is considered investigational. Investigational services are specific contract exclusions in most member benefit certificates of coverage.
Use of the Aveir single-chamber transcatheter pacing system for all indications does not meet primary coverage criteria that there be scientific evidence of effectiveness. For contracts without primary coverage criteria, use of the Aveir single-chamber transcatheter pacing system for all indications is considered investigational. Investigational services are specific contract exclusions in most member benefit certificates of coverage.
Leadless left ventricular pacing does not meet primary coverage criteria that there be scientific evidence of effectiveness. For contracts without primary coverage criteria, use of leadless left ventricular pacing is considered investigational. Investigational services are specific contract exclusions in most member benefit certificates of coverage.
Leadless bi-ventricular pacing does not meet primary coverage criteria that there be scientific evidence of effectiveness. For contracts without primary coverage criteria, use of leadless bi-ventricular pacing is considered investigational. Investigational services are specific contract exclusions in most member benefit certificates of coverage.
Effective October 15, 2022 through May 2023
Meets Primary Coverage Criteria Or Is Covered For Contracts Without Primary Coverage Criteria
Micra single-chamber transcatheter pacing system meets primary coverage criteria when all of the following are met:
Does Not Meet Primary Coverage Criteria Or Is Not Covered For Contracts Without Primary Coverage Criteria
Use of the Micra single-chamber transcatheter pacing system for any indication or condition not described above, does not meet primary coverage criteria that there be scientific evidence of effectiveness. For contracts without primary coverage criteria, use of the Micra single-chamber transcatheter pacing system for any indication or condition not described above is considered investigational. Investigational services are specific contract exclusions in most member benefit certificates of coverage.
Use of the Aveir single-chamber transcatheter pacing system for all indications does not meet primary coverage criteria that there be scientific evidence of effectiveness. For contracts without primary coverage criteria, use of the Aveir single-chamber transcatheter pacing system for all indications is considered investigational. Investigational services are specific contract exclusions in most member benefit certificates of coverage.
Leadless left ventricular pacing does not meet primary coverage criteria that there be scientific evidence of effectiveness. For contracts without primary coverage criteria, use of leadless left ventricular pacing is considered investigational. Investigational services are specific contract exclusions in most member benefit certificates of coverage.
Leadless bi-ventricular pacing does not meet primary coverage criteria that there be scientific evidence of effectiveness. For contracts without primary coverage criteria, use of leadless bi-ventricular pacing is considered investigational. Investigational services are specific contract exclusions in most member benefit certificates of coverage.
Effective August 2019 through October 15, 2022
Meets Primary Coverage Criteria Or Is Covered For Contracts Without Primary Coverage Criteria
Micra Transcatheter Pacing System meets primary coverage criteria when all of the following are met:
Does Not Meet Primary Coverage Criteria Or Is Not Covered For Contracts Without Primary Coverage Criteria
Use of a leadless pacemaker for all other indications, does not meet primary coverage criteria that there be scientific evidence of effectiveness. For contracts without primary coverage criteria, use of a leadless pacemaker implant for all other indications is considered investigational. Investigational services are specific contract exclusions in most member benefit certificates of coverage.
Leadless left ventricular pacing does not meet primary coverage criteria that there be scientific evidence of effectiveness. For contracts without primary coverage criteria, use of leadless left ventricular pacing is considered investigational. Investigational services are specific contract exclusions in most member benefit certificates of coverage.
Leadless bi-ventricular pacing does not meet primary coverage criteria that there be scientific evidence of effectiveness. For contracts without primary coverage criteria, use of leadless bi-ventricular pacing is considered investigational. Investigational services are specific contract exclusions in most member benefit certificates of coverage.
Effective Prior to August 2019
Meets Primary Coverage Criteria Or Is Covered For Contracts Without Primary Coverage Criteria
Micra Transcatheter Pacing System meets primary coverage criteria when all of the following are met:
Does Not Meet Primary Coverage Criteria Or Is Not Covered For Contracts Without Primary Coverage Criteria
Use of a leadless pacemaker for all other indications, does not meet primary coverage criteria that there be scientific evidence of effectiveness. For contracts without primary coverage criteria, use of a leadless pacemaker implant for all other indications is considered investigational. Investigational services are specific contract exclusions in most member benefit certificates of coverage.
Leadless left ventricular pacing does not meet primary coverage criteria that there be scientific evidence of effectiveness. For contracts without primary coverage criteria, use of leadless left ventricular pacing is considered investigational. Investigational services are specific contract exclusions in most member benefit certificates of coverage.
Leadless bi-ventricular pacing does not meet primary coverage criteria that there be scientific evidence of effectiveness. For contracts without primary coverage criteria, use of leadless bi-ventricular pacing is considered investigational. Investigational services are specific contract exclusions in most member benefit certificates of coverage.
Effective Prior to January 2019
Meets Primary Coverage Criteria Or Is Covered For Contracts Without Primary Coverage Criteria
Micra Transcatheter Pacing System meets primary coverage criteria when all of the following are met:
Does Not Meet Primary Coverage Criteria Or Is Not Covered For Contracts Without Primary Coverage Criteria
Use of the Micra Transcatheter Pacing System for all other indications, does not meet primary coverage criteria that there be scientific evidence of effectiveness. For contracts without primary coverage criteria, use of a leadless pacemaker implant for all other indications is considered investigational. Investigational services are specific contract exclusions in most member benefit certificates of coverage.
|
|
|
|
| Rationale: |
This evidence review was created in August 2018 with a search of the MEDLINE database through July 18, 2018.
Evidence reviews assess the clinical evidence to determine whether the use of a technology improves the net health outcome. Broadly defined, health outcomes are length of life, quality of life, and ability to function--including benefits and harms. Every clinical condition has specific outcomes that are important to patients and to managing the course of that condition. Validated outcome measures are necessary to ascertain whether a condition improves or worsens; and whether the magnitude of that change is clinically significant. The net health outcome is a balance of benefits and harms.
To assess whether the evidence is sufficient to draw conclusions about the net health outcome of a technology, 2 domains are examined: the relevance and the quality and credibility. To be relevant, studies must represent 1 or more intended clinical use of the technology in the intended population and compare an effective and appropriate alternative at a comparable intensity. For some conditions, the alternative will be supportive care or surveillance. The quality and credibility of the evidence depend on study design and conduct, minimizing bias and confounding that can generate incorrect findings. The randomized controlled trial (RCT) is preferred to assess efficacy; however, in some circumstances, nonrandomized studies may be adequate. RCTs are rarely large enough or long enough to capture less common adverse events and long-term effects. Other types of studies can be used for these purposes and to assess generalizability to broader clinical populations and settings of clinical practice.
Conventional pace makers systems have been in use for over 50 years and the current available technology has matured with significant similarities of device design across models. Extensive bench testing experience with conventional pacemakers and a good understanding of operative and early postimplant safety and effectiveness is available which limits the need for collection of clinical data to understand their safety and effectiveness with regard to implant, tip fixation, electrical measures, and rate response. As such, a randomized trial comparing the leadless pacemakers with conventional pacemakers was not required by the Food and Drug Administration (FDA).
INDIVIDUALS WITH GUIDELINES-BASED INDICATION FOR A VENTRICULAR PACING SYSTEM WHO ARE MEDICALLY ELIGIBLE TO RECEIVE A CONVENTIONAL PACING SYSTEM
Clinical Context and Therapy Purpose
The purpose of Micra Transcatheter Pacing System in patients with a class I or II guidelines-based indication for implantation of a single chamber ventricular pacemaker is to provide a treatment option that is an alternative to or an improvement on conventional pacing systems.
The question addressed in this evidence review is: Does use of the Micra Transcatheter Pacing System improve the net health outcome in patients with patients with a class I or II guidelines-based indication for implantation of a single-chamber ventricular pacemaker who are medically eligible to receive a conventional pacing systems?
The following PICOTS were used to select literature to inform this review.
Patients
The relevant population of interest is patients with a class I or II guidelines-based indication for implantation of a single chamber ventricular pacemaker who are medically eligible to receive conventional pacing system.
Interventions
The therapy being considered is the Micra Transcatheter Pacing System.
Comparators
The following therapy is currently being used to make decisions about managing patients requiring a pacemaker: a conventional pacemaker.
Outcomes
The general outcomes of interest are treatment-related mortality and morbidity. Specifically, the short-term outcomes include acute complication-free survival rate, electrical performance of the device including pacing capture threshold and adverse events including procedural and postprocedural complications. Long-term outcomes include chronic complication-free survival rate, electrical performance of the device including pacing impedance and pacing thresholds and chronic complications including any system explant, replacement (with and without system explant) and repositions. Further, analysis summary statistics regarding battery length are deemed crucial as well.
Timing
To assess short-term safety, the first 30 days postimplant is generally considered appropriate as majority of device and procedural complications occur within this time frame. To assess long-term efficacy and safety as well issues related to end of life of the device, follow up to 9 to 12 years postimplant with
adequate sample size are required to characterize device durability and characterize infrequent complications with sufficient certainty.
Setting
Cardiac pacemaker implant is performed by interventional cardiologists in the electrophysiology laboratory.
Nonrandomized Controlled Trials
Pivotal Trial
The pivotal investigational device exemption (IDE) trial was a prospective single cohort study in which 744 patients with class I or II indication for implantation of a single chamber ventricular pacemaker according to ACC/AHA/HRS 2008 guidelines and any national guidelines were enrolled. The details on the design (Ritter, 2015) and results of the IDE trial have been published (Ritter, 2015; Reynolds, 2016).. System performance from the pivotal trial has been published (Lloyd, 2017) but results are not discussed further.
Of the 744 patients, the implantation of the Micra Transcatheter Pacing System was attempted in 725 patients of whom 719 (99.2%) were successfully implanted. The demographics of the trial population were typical for a single chamber pacemaker study performed in the United States with 42% being female and average age was 76 years. Sixty-four percent had a pacing indication associated with persistent or permanent atrial arrhythmias, 72.6% had any atrial fibrillation at baseline, and 27.4% did not have a history of atrial fibrillation. Among those 27.4% (n=199) without atrial fibrillation, 16.1% (n=32) had a primary indication of sinus bradycardia and 3.5% (n=7) had a primary indication of tachycardia-bradycardia (Reynolds, 2016).
The IDE trial had 2 primary end points related to safety and efficacy. The trial would have met the safety end point if the lower bound of the 95% confidence interval (CI) for the rate of freedom from major complications related to the Micra Transcatheter Pacing System or implantation procedure exceeded 83% at 6 months. Major complications were defined as those resulting in any of the following; death, permanent loss of device function due to mechanical or electrical dysfunction of the device (eg, pacing function disabled, leaving device abandoned electrically), hospitalization, prolonged Hospitalization by at least 48 hours or system revision (reposition, replacement, explant) (FDA, 2018). The trial would have met the efficacy end point if the lower bound of the 95% CI for the proportion of patients with adequate pacing capture thresholds (PCT) exceeded 80% at 6 months. PCT as an effectiveness objective is a common electrical measure of pacing efficacy and is consistent with recent studies. Pacing capture threshold measured in volts is defined as the minimum amount of energy needed to capture the myocardial tissue electrically. Unnecessary high pacing output adversely shortens the battery life of the pacemaker and is influenced by physiologic and pharmacologic factors (FDA, 2018). As per FDA, demonstrating that “PCT is less than 2 Volts for the vast majority of subjects will imply that the Micra Transcatheter Pacing System will have a longevity similar to current pacing systems since Micra’s capture management feature will nominally set the safety margin to 0.5 volts above the PCT with hourly confirmation of the PCT” (FDA, 2018).
At 6 months, the trial met both the efficacy and safety primary end points including freedom from major complications related to the system or procedure in 96.0% of the patients (95% CI, 93.9% to 97.3%), compared with a performance goal of 83%, and an adequate pacing capture threshold in 98.3% of the patients (95% CI, 96.1% to 99.5%), compared with a performance goal of 80% (Reynolds, 2016).
The results of the IDE trial were compared post hoc with a historical cohort of 2667 patients generated from the six previous pacemaker studies conducted between 2005 and 2012 by Medtronic that evaluated performance requirement at 6 months post implant of right ventricle pacing leads (single-chamber rates obtained by excluding any adverse events that were only related to the right atrial lead from the analysis). Micra Transcatheter Pacing System was associated with fewer complication than the historical control (4.0% vs 7.4%; hazard ratio [HR], 0.49; 95% CI, 0.33 to 0.75; p=0.001) (Reynolds, 2016). Because there were differences in the baseline patient characteristics between the 2 cohorts (patients in the historical cohort were younger and with lower prevalence of coexisting conditions vs the IDE trial), an additional propensity-matched analysis was also conducted that showed similar result (HR=0.46; 95% CI, 0.28 to 0.74). As per FDA, lower rate of major complication with Micra Transcatheter Pacing System were driven by reductions in access site events (primarily implant site hematoma and implant site infections), pacing issues (primarily device capture and device pacing issues), and fixation events (there were no device/lead dislodgements in the Micra IDE trial) (FDA, 2016).
While the overall rate of complication was low, the rate of major complications related to cardiac injury (ie., pericardial effusion or perforation) was higher in the Micra IDE trial than in the 6 reference Medtronic pacemaker studies (1.6% vs 1.1%, p=0.288). Thus, there appears to be a trade-off between types of adverse events with Micra Transcatheter Pacing System and conventional pacemakers. While adverse events related to leads and pocket are eliminated or minimized with Micra Transcatheter Pacing System, certain adverse events such as groin vascular complications and vascular/cardiac bleeding occur at a higher frequency or are additive (new events) than conventional pacemakers. Of these, procedural complications such as acute cardiac perforations that were severe enough to resulting result in tamponade and emergency surgery were most concerning (FDA, 2016).
In addition to lack of adequate data on long-term safety, effectiveness, reliability, and incidence of late device failures and battery longevity, there is also inadequate clinical experience with issues related to devices that have reached end of life including whether to extract or leave the device in situ and possibility of device-device interactions (FDA, 2016). There is no data on device-device interactions (both electrical and mechanical), which may occur when there is a deactivated Micra device alongside another leadless pacemaker or when a leadless pacemaker and transvenous device are both present. Even though, there have only been few device retrievals and very limited experience with time course of encapsulation of these devices in humans, it is highly likely that these devices will be fully encapsulated by the end of its typical battery life, and therefore device retrieval is unlikely.19 Current recommendations for end-of-device-life care for a Micra device may include the addition of a replacement device with or without explantation of the Micra device, which should be turned off (Medtronic, 2018).
Post Approval Study
The FDA approval of the Micra Transcatheter Pacing System is contingent on multiple postapproval studies to ensure reasonable assurance of continued safety and effectiveness of the device. Among these, the Micra Transcatheter Pacing System Post-Approval Study, a global, prospective, observational, multi-center study, enrolled 1830 patients to ensure that data is available for 1741 patients to estimate acute complication rate within 30 day of the implant, 500 patients to estimate 9-year complication free survival rate, and a minimum of 200 patients with a Micra Transcatheter Pacing System revision for characterizing end of device service.18 As per the protocol, if a subsequent device is placed and the Micra is deactivated or explanted, Medtronic would contact the implanting center and request the patient's clinical data surrounding the revision. All such data would be summarized including the type of system revision, how the extraction was attempted, success rate, and any associated complications (FDA, 2016).
The postapproval study completed enrollment in early March 2018. The definition of major complication in the postapproval study was same as the Micra IDE trial. It is unclear if any patients who participated in the IDE trial were also enrolled in the post approval study.
At 30 days, the major complication rate was 1.51% (95% CI, 0.78 to 2.62%). The major complication rate was lower in the postapproval study compared with IDE trial (odds ratio [OR], 0.58; 95% CI, 0.27 to 1.25) although this did not reach statistical difference. The lower major complications was associated with a
decrease in events that led to hospitalization, prolonged hospitalization, or loss of device function in the postapproval study compared to the IDE trial (Roberts, 2017).
After a mean follow-up of 6.8 months, the major complication rate was 2.7% (95% CI, 2.0% to 3.6%). Authors compared these results with the same historical cohort of 2667 patients used in the IDE trial and reported a 63% reduction in the risk for major complications through 12 months with Micra Transcatheter Pacing System relative to conventional pacemakers (HR=0.37; 95% CI, 0.27 to 0.52). Additionally, the risk for major complication was lower in the Micra postapproval study than in the IDE trial but it was statistically significant different (HR= 0.71, 95% CI, 0.44 to 1.1) (Mikhael, 2018). However, details of events classified as major complications were not reported for the historical control or for the IDE trial cohort at 1 year and therefore it is unclear as to which events were decreased in the post approval study or if any events increased with Micra Transcatheter Pacing System.
Section Summary: Individuals With Guidelines-Based Indication for a Ventricular Pacing System who are Medically Eligible to Receive a Conventional Pacing System
The evidence for use of Micra Transcatheter Pacing System consists of a pivotal prospective cohort study and a postapproval prospective cohort study. Results at 6 months and 1 year for the pivotal study reported high procedural success (above 99%) and device effectiveness (pacing capture threshold met in 98% patients). Majority of the system or procedural-related complications occur within 30 days. At 1 year, the incidence of major complication did not increase substantially from 6 months (3.5% at 6 months versus 4% at 1 year). Results of the postapproval study were consistent with pivotal study and showed a lower incidence of major complications at -30 days as well as 1 year (1.5% and 2.7%, respectively). In both studies, the point estimates of major complication were lower than the pooled estimates from 6 studies of conventional pacemakers used as a historical comparator. While Micra Transcatheter Pacing System eliminates adverse events associated with lead and pocket issue, its use results in additional complication related to the femoral access site (groin hematomas and access site bleeding) and implantation/release of the device (traumatic cardiac injury). Considerable uncertainties and unknowns remain in terms of durability of device and end of life device issues. Early and limited experience suggests that retrieval of these devices is unlikely because in due course of time, the devices will be encapsulated. There is limited data on device-device interactions (both electrical and mechanical), which may occur when there is a deactivated Micra device alongside another leadless pacemaker or when a leadless pacemaker and transvenous device are both present.
INDIVIDUALS WITH GUIDELINES-BASED INDICATION FOR A VENTRICULAR PACING SYSTEM WHO ARE MEDICALLY INELIGIBLE FOR A CONVENTIONAL PACING SYSTEM
Clinical Context and Therapy Purpose
The purpose of Micra Transcatheter Pacing System in patients with a class I or II guidelines-based indication for implantation of a single chamber ventricular pacemaker is to provide a treatment option that is an alternative to or an improvement on conventional pacing systems.
The question addressed in this evidence review is: Does use of the Micra Transcatheter Pacing System improve the net health outcome in patients with patients with a class I or II guidelines-based indication for implantation of a single chamber ventricular pacemaker who are medically ineligible for a conventional pacing system?
The following PICOTS were used to select literature to inform this review.
Patients
The relevant population of interest is patients with a class I or II guidelines-based indication for implantation of a single chamber ventricular pacemaker who are medically ineligible for a conventional pacing system.
Interventions
The therapy being considered is Micra Transcatheter Pacing System.
Comparators
The following therapy and practice are currently being used to make decisions about managing patients ineligible for a conventional pacemaker: medical management and/or conventional pacemakers.
Outcomes
The general outcomes of interest are treatment-related mortality and morbidity. Specifically, the short-term outcomes include acute complication-free survival rate, electrical performance of the device including pacing capture threshold and adverse events including procedural and postprocedural
complications. Long-term outcomes include chronic complication-free survival rate, electrical performance of the device including pacing impedance and pacing thresholds and chronic complications including any system explant, replacement (with and without system explant) and repositions. Further, analysis summary statistics regarding battery length are deemed crucial as well.
Timing
To assess short-term safety, the first 30 days postimplant is generally considered appropriate as majority of device and procedural complications occur within this time frame. To assess long-term efficacy and safety as well issues related to end of life of the device, follow up to 9 to 12 years postimplant with adequate sample size are required to characterize device durability and characterize infrequent complications with sufficient certainty.
Setting
Cardiac pacemaker implant is performed by interventional cardiologists in the electrophysiology laboratory.
Nonrandomized Controlled Trials
No studies that exclusively enrolled patients who were medically ineligible to receive a conventional pacing system were identified.
In the IDE trial, 6.2% or 45 patients received the Micra Transcatheter Pacing System because they were medically ineligible to receive a conventional pacing system such as compromised venous access, the need to preserve veins for hemodialysis, thrombosis, a history of infection, or the need for an indwelling venous catheter.
In the postapproval registry whose early results have been published only as an abstract, authors reported stratified results of 99 of 1744 patients who had previous cardiac implantable electronic device (CIED) infection (Mikhael, 2018). Of these 99, 78 (79%) were classified as medically ineligible to receive a conventional pacemaker in the opinion of physician. A stratified analysis of these 78 patients was not presented in the abstract. In this cohort of patients with CIED infection, Micra was implanted successfully in 98 patients and the previous CIED was explanted the same day as Micra was implanted in 36% of patients. Major complications were reported in 2% of patients with an average follow-up of 5.5 months. Six deaths were reported but none was related to the Micra Transcatheter Pacing System or the procedure.
Section Summary: Individuals with Guidelines-Based Indication for a Ventricular Pacing System who are Medically Ineligible for a Conventional Pacing System
No studies that exclusively enrolled patients who were medically ineligible to receive a conventional pacing system were identified. However, a subgroup of patients in whom use of conventional pacemakers was precluded was enrolled in the pivotal as well as the postapproval trial. Information on the outcomes in these subgroups of patients from the postapproval study showed that Micra was successfully implanted in 98% of cases and safety outcomes were similar to the original cohort. Even though, the evidence is limited and long-term effectiveness and safety is unknown, the short-term benefits outweigh the risks as the complex tradeoff of adverse events for these devices need to be assessed in the context of lifesaving potential of pacing systems in patients who are ineligible for conventional pacing systems on the market.
SUMMARY OF EVIDENCE
For individuals with guidelines-based indication for a ventricular pacing system who are medically eligible to receive a conventional pacing system who are treated with Micra transcatheter pacing system, the evidence includes a pivotal prospective cohort study a 1 postapproval prospective cohort study. Relevant outcomes are other test performance, treatment-related mortality, and treatment-related morbidity. Results at 6 months and 1 year for the pivotal study reported high procedural success (above 99%) and device effectiveness (pacing capture threshold met in 98% patients). Majority of the system or procedural-related complications occur within 30 days. At 1 year, the incidence of major complication did not increase substantially from 6 months (3.5% at 6 months vs 4% at 1 year). Results of the postapproval study were consistent with pivotal study and showed a lower incidence of major complications at -30 days as well as 1 year (1.5% and 2.7%, respectively). In both studies, the point estimates of major complication were lower than the pooled estimates from 6 studies of conventional pacemakers used as a historical comparator. While Micra Transcatheter Pacing System eliminates lead- and surgical pocket-related complications, its use can result in potentially more serious complication related to implantation/release of the device (traumatic cardiac injury) and less serious complications related to the femoral access site (groin hematomas and access site bleeding). Considerable uncertainties and unknowns remain in terms of durability of device and end of life device issues. Early and limited experience suggests that retrieval of these devices is unlikely because, in due course, the devices will be encapsulated. There is limited data on device-device interactions (both electrical and mechanical), which may occur when there is a deactivated Micra device alongside another leadless pacemaker or when a leadless pacemaker and transvenous device are both present. While the current evidence is encouraging, overall benefit with broad use of Micra transcatheter pacing system compared to conventional pacemakers has not been shown. The evidence is insufficient to determine the effects of technology on health outcomes.
For individuals with guidelines-based indication for a ventricular pacing system who are medically ineligible for a conventional pacing system who are treated with Micra transcatheter pacing system, the evidence includes subgroup analysis of a pivotal prospective cohort study and a postapproval prospective cohort study. Relevant outcomes are other test performance, treatment-related mortality, and treatment-related morbidity. Information on the outcomes in the subgroup of patients from the postapproval study showed that Micra was successfully implanted in 98% of cases and safety outcomes were similar to the original cohort. Even though, the evidence is limited and long-term effectiveness and safety is unknown, the short-term benefits outweigh the risks as the complex tradeoff of adverse events for these devices need to be assessed in the context of lifesaving potential of pacing systems in patients who are ineligible for conventional pacing systems. The evidence is sufficient to determine that the technology results in a meaningful improvement in the net health outcome.
SUPPLEMENTAL INFORMATION
PRACTICE GUIDELINES AND POSITION STATEMENTS
American College of Cardiology Foundation et al
The American College of Cardiology Foundation, American Heart Association, and Heart Rhythm Society’s focused update (2012) on device-based therapy of cardiac rhythm abnormalities incorporated into their joint 2008 guidelines for device-based therapy of cardiac rhythm abnormalities does not include recommendations on leadless cardiac pacemakers (Epstein, 2013).
The 2012 Heart Rhythm Society and American College of Cardiology Foundation expert consensus statement on pacemaker device and mode selection did not include recommendations on leadless cardiac pacemakers (Gillis, 2012).
ONGOING AND UNPUBLISHED CLINICAL TRIALS
Some currently unpublished trials that might influence this review are listed below:
Planned Enrollment 100 Completion Date: Nov 2021
Planned Enrollment 3100 Completion Date: Aug 2026
2019 Update
Annual policy review completed with a literature search using the MEDLINE database through August 2019. No new literature was identified that would prompt a change in the coverage statement.
2020 Update
Annual policy review completed with a literature search using the MEDLINE database through August 2020. No new literature was identified that would prompt a change in the coverage statement.
2021 Update
Annual policy review completed with a literature search using the MEDLINE database through August 2021. No new literature was identified that would prompt a change in the coverage statement.
2022 Update
Annual policy review completed with a literature search using the MEDLINE database through April 2022. No new literature was identified that would prompt a change in the coverage statement. The key literature is summarized below.
Aveir Leadless Pacemaker
The pivotal investigational device exemption (IDE) trial of the Aveir leadless pacemaker (LEADLESS II - Phase 2; NCT04559945) was a multicenter, prospective single cohort study enrolling 200 patients with a guidelines-based indication for single-chamber pacing (FDA, 2022). Primary results from the IDE trial have been summarized in a published research correspondence and FDA documents (Reddy, 2022; FDA, 2022).
Implantation of the Aveir leadless pacing system was successful in 196/200 (98%) trial subjects (mean age, 75.6 years; 37.5% female). The primary indication for pacing was chronic atrial fibrillation with 2nd or 3rd degree atrioventricular block (52.5%). The trial had 2 primary endpoints related to safety and efficacy. The trial would meet its safety endpoint if the lower bound of the 97.5% CI for the complication-free rate exceeded 86% at 6 weeks. A complication was defined as a device-or-procedure-related serious adverse event, including those that prevented initial implantation. The trial would meet its efficacy endpoint if the lower bound of the 97.5% CI for the composite success rate exceeded 85% at 6 weeks. The confirmatory effectiveness endpoint was considered met if the pacing threshold voltage is less than or equao to 2.0 V at 0.4 ms and the sensed R-wave amplitude is either greater than or equal to 5.0 mV at the 6-week visit or greater than or equal to the value at implant.
At 6 weeks, the trial met both of its confirmatory safety and efficacy endpoints, including freedom from device-or-procedure-related complications in 96% of patients (95% CI, 92.2 to 98.2), compared with a performance goal of 86%, and a composite success rate of 95.9% of patients (95% CI, 92.1 to 98.2), compared with a performance goal of 85%. The 6-month complication-free rate was 94.9% (95% CI, 90.0 to 97.4). The most frequent complications included 3 cardiac tamponade events and 3 premature deployment events. The rate of cardiac perforation/tamponade/pericardial effusion was 1.5%. No dislodgement events were reported in the Aveir cohort.
Confirmatory secondary endpoints included assessment of an appropriate and proportional rate-response during a Chronotropic Assessment Exercise Protocol (CAEP) exercise protocol and an estimated 2-year survival rate. The CAEP assessment was initiated in 23 subjects, of which 17 were considered analyzable. The rate-response slope was 0.93 (95% CI, 0.78 to 1.08), which fell within the prespecified range of 65% to 135%. The estimated 2-year survival rate based on the Nanostim Phase 1 cohort (N=917) was 85.3% (95% CI, 82.7 to 87.4), which exceeded the performance goal of 80%.
The current evidence on the use of the Aveir device is limited by a lack of adequate data on quality of life, long-term safety, effectiveness, reliability, and incidence of late device failures and battery longevity. While the device is designed to be retrieved when therapy needs evolve or the device needs to be replaced, there is currently inadequate clinical experience with issues related to devices that have reached end-of-life. Survival data for the currently marketed version of the Aveir device has not been reported.
Continued FDA approval of the Aveir transcatheter pacing system is contingent on the results of the Aveir VR Real-World Evidence Study (FDA, 2022). This post-approval study is designed to evaluate the long-term safety of the Aveir device in a real-world sample of 2100 participants. Both acute and long-term safety will be evaluated as post implant complication-free rates at 30-days and 10-years. Six-month and 10-year reports are due in September 2022 and March 2032, respectively.
2023 Update
Annual policy review completed with a literature search using the MEDLINE database through June 2023. No new literature was identified that would prompt a change in the coverage statement. The key identified literature is summarized below.
Three year outcomes from the Micra Coverage with Evidence Development study were published by Crossley et al in 2023 (Crossley, 2023). Patients implanted with leadless pacemakers had a 32% lower rate of chronic complications (HR, 0.68; 95% CI, 0.59 to 0.78; p<.001) and a 41% lower rate of any reinterventions compared to patients receiving a transvenous pacemaker (HR, 0.59; 95% CI, 0.44 to 0.78; p=.0002). Use of a leadless system was also associated with a 49% lower rate (p=.01) of upgrades to a dual-chamber system and a 35% lower rate (p=.002) of upgrades to cardiac resynchronization therapy. Heart failure hospitalizations at 3 years were slightly, but significantly lower in adjusted time-to-event models (HR, 0.90; 95% CI, 0.83 to 0.97; p=.005) in patients receiving a leadless system. All-cause mortality rates at 3 years between leadless and transvenous systems were not significantly different after accounting for differences in baseline characteristics (HR, 0.97; 95% CI, 0.92 to 1.03; p=.32). No significant differences in the composite endpoint of time to heart failure hospitalization or death were observed for the original full cohort (p=.28) or in a subgroup of patients without a history of heart failure (p=.98).
Chinitz et al conducted a prospective, single-arm study (AccelAV) at 20 sites in the United States and Hong Kong to assess the efficacy of the Micra AV leadless pacemaker in promoting atrioventricular synchrony (AVS) in adults with a history of atrioventricular (AV) block (n=157) (Chinitz, 2023). This device uses an accelerometer and detection algorithm to mechanically sense atrial contractions to facilitate VDD pacing and AVS in individuals with normal sinus function. Based on a preliminary feasibility study (MARVEL 2), a sample size of 150 individuals was expected to provide at least 50 individuals with complete AV block and normal sinus function to permit estimation of AVS. Micra AV implantation and completion of the 1-month study visit was achieved by 139 individuals, of which 54 (mean age, 77 years; 55.6% female) comprised the intended use population with a predominant heart rhythm of complete AV block with normal sinus rhythm (Steinwender, 2020). The primary endpoint was the rate of AVS during a 20-minute resting period at 1 month postimplant in these patients. Atrioventricular synchronous pacing was defined as a ventricular marker preceding a P wave within 300 ms, regardless of the underlying cardiac rhythm. Secondary endpoints included stability of AVS during rest between 1 and 3 months, percent AVS during a 24-hr ambulatory period at 1 months and change in stroke volume. Quality of life was also measured with the EQ-5D-3L health status assessment. At 1 month, AVS percentage at rest was 85.4% (95% CI, 81.1% to 88.9%; median, 90.0%) during VDD pacing, with 85.2% of patients achieving >70% resting AVS. At the 3-month visit, 37/54 remained in the same rhythm. Among these subjects, no significant change in AVS synchrony was detected (p=.43) between the 3-month (mean, 84.1%; 95% CI, 78.3% to 88.6%) and 1-month visits (mean, 84.1%; 95% CI, 81.2% to 89.9%). At the 1 month visit, average 24-hour ambulatory AVS was 74.5% (95% CI, 70.4% to 78.2%). EQ-5D-3L health status scores significantly improved by 0.07 points between baseline and 3 months (p=.031) among patients with complete AV block and normal sinus function. Ambulatory AVS percentage significantly increased from 71.9% to 82.6% (p<.001) in twenty patients who participated in a substudy at a mean follow-up of 9.5 months designed to characterize the impact of optimized device programming. Improvement in AVS was most evident during elevated sinus rates between 80 and 110 bpm. In the safety cohort (n=152), there were 14 major complications, including 4 pericardial effusions and 2 heart failure events. One pericardial effusion resulted in perforation and death in a 92-year-old woman with high baseline risk. A second death was reported in an 83-year-old man at 127 days postimplant but was not considered system- or procedure-related. No device upgrades and 1 device explantation and replacement was reported during follow-up. Study interpretation is limited by lack of a comparator group and short duration of follow-up. The ongoing Micra AV Post-Approval Registry (NCT04253184) has follow-up planned through 3 years. The investigators also noted that the AVS percentage required to maintain a clinical benefit over time is unknown, but likely is not 100%.
Reddy et al reported 1-year outcomes from the LEADLESS II IDE trial (Reddy, 2023). Confirmatory safety and efficacy endpoints at 1 year were both met for European regulatory approval, including freedom from device-or-procedure-related complications in 93.2% of patients (95% CI, 88.7% to 95.9%), compared with a performance goal of 83%, and a composite success rate of 95.1% (95% CI, 91.2% to 97.6%), compared with a performance goal of 80%. Most complications (11 of 15) were reported within the first 3 days post-implantation, including 4 cardiac tamponade events, 3 premature deployments with or without device migration, 2 access site bleeding events, 1 pulmonary embolism, and 1 case of deep vein thrombosis. Four long-term complications were reported between 3.8 and 9.5 months post-implantation, including 2 cases of heart failure and 2 cases of pacemaker-induced cardiomyopathy. Based on the device-use conditions in this analysis cohort, the investigators estimate that mean device battery longevity is 17.6 ± 6.6 years (95% CI, 16.6 to 18.6).
2024 Update
Annual policy review completed with a literature search using the MEDLINE database through May 2024. No new literature was identified that would prompt a change in the coverage statement. The key identified literature is summarized below.
Garweg et al conducted a prospective, un-blinded, randomized, noninferiority, single center study (N=51) comparing outcomes in individuals implanted with a single-chamber Micra leadless pacemaker (n=27) or a conventional single-chamber ventricular pacemaker (n=24) (Garweg, 2023). The primary endpoints were related to mechanical outcomes, including change in left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS) during a 12-month follow up period. At 12 months, both groups showed similar worsening in left ventricular function. The change in LVEF was -10 ± 7.3% in the Micra group and -13.4 ± 9.9% in the conventional group (p=.218). The change in GLS was 5.7 ± 6.4 in the Micra group and 5.2 ± 3.2 in the conventional group (p=.778). For the secondary endpoints, the Micra group had no significant change in tricuspid (p=.195) and mitral (p=.460) valve function and the conventional group had significant worsening in tricuspid (p=.001) and mitral (p=.017) valve function over 12 months. Change in valve function over 12 months between the groups was significantly different for the tricuspid valve (p=.009) and not significantly different for the mitral valve (p=.304). Median N-terminal-pro hormone B-type natriuretic peptide levels at 12 months was lower in the Micra group (970 pg/dL) compared to the conventional group (1394 pg/dL) (p=.041). For electrical performance, over 12 months the Micra group had higher impedance (p<.001) and lower pacing threshold (p<.001) compared to the conventional group, however there was no interaction between time and intervention. All implant procedures for both groups were successful, with no acute major complications. The authors conclude that Micra is non inferior to conventional pacemakers, with comparable impacts on ventricular function and less valvular dysfunction.
El-Chami et al reported results on a 5-year follow-up of the Micra PAR study (El-Chami, 2024). Major complication rates for individuals with an attempted Micra VR implant procedure (n=1809) was 4.47% (95% CI, 3.6% to 5.5%) at 60 months and there were no Micra removals due to infection reported during follow-up. The authors concluded that low rates of major complications, low incidence of infection, and low rates of system revisions have been reported in long-term follow-up.
Roberts et al conducted a prospective, single-arm study of the Micra Acute Performance European and Middle Eastern (MAP EMEA) registry and compared results to the IDE and PAR studies (Roberts, 2023). The primary endpoint was 30-day major complication rate. For the MAP EMEA individuals (N=928) at 30 days there were 24 major complications in 24 individuals (2.59%; 95% CI, 1.66% to 3.82%). Of these events, 10 were at the groin and puncture site, 6 cardiac effusion/perforation events, 4 device pacing issues, 3 infection events (2 resulting in system revisions), and 1 event of hemodynamic instability. Through study follow-up after 30 days (mean duration, 9.7 ± 6.5 months), there were 11 more major complications in 9 individuals adjudicated as related to the Micra VR device or procedure. The MAP EMEA cohort, compared to the IDE (N=726) and PAR (N=1811) study cohorts, had less heart failure (8.3% vs. 18.0% vs. 13.0%, p<.001) and coronary artery disease (19.9% vs. 28.2% vs. 22.0%, p<.001) and were more likely to have renal dysfunction (28.9% vs. 20.5% vs. 21.5%, p<.001) and be on dialysis (10.2% vs. 3.9% vs. 7.9%, p<.001). However, a limitation of this comparison is the median duration of follow-up varied among the MAP EMEA, IDE, and PAR study cohorts (9.6, 19.6, and 34.2 months, respectively).
Boveda et al reported 2-year outcomes from the Micra CED study in a subgroup of individuals at higher risk of pacemaker complications (Boveda, 2023). Participants were considered high-risk if they had a diagnosis of chronic kidney disease Stages 4 to 5, end-stage renal disease, malignancy, diabetes, tricuspid valve disease (TVD), or chronic obstructive pulmonary disease (COPD) 12 months prior to implant. They compared outcomes between high-risk individuals with leadless-VVI pacemakers (n=9858) and transvenous-VVI pacemakers (n=12157). The leadless-VVI group had fewer complications compared to the transvenous-VVI group in those with malignancy (HR, 0.68; adjusted CI, 0.48 to 0.95), diabetes (HR, 0.69; adjusted CI, 0.53 to 0.89), TVD (HR, 0.60; adjusted CI, 0.44 to 0.82), and COPD (HR, 0.73; adjusted CI, 0.55 to 0.98), had fewer reinterventions in those with diabetes (HR, 0.58; adjusted CI, 0.37 to 0.89), TVD (HR, 0.46; adjusted CI, 0.28 to 0.76), and COPD (HR, 0.51; adjusted CI, 0.29 to 0.90), and lower rates of combined outcome of device complications and select reinterventions in those with malignancy (HR, 0.52; adjusted CI, 0.32 to 0.83), diabetes (HR, 0.52; adjusted CI, 0.35 to 0.77), TVD (HR, 0.44; adjusted CI, 0.28 to 0.70), and COPD (HR, 0.55; adjusted CI, 0.34 to 0.89). The authors conclude that in this real-world study, individuals with leadless pacemakers had lower 2-year complications and reinterventions rates than individuals with transvenous pacemakers in several high-risk subgroups.
Crossley et al reported outcomes from the Micra AV Coverage with Evidence Development study comparing individuals implanted with Micra AV (n=7471) to a comparator cohort (n=107,800) of individuals implanted with a dual-chamber transvenous pacemaker regardless of pacing indication (Crossley, 2024). At 30 days, the adjusted overall complications were 8.6% for Micra AV group and 11.0% for dual chamber transvenous group (p<.0001) and the adjusted all-cause mortality was 6.0% for the Micra AV group and 3.5% for the dual chamber transvenous group (p<.0001). At 6 months, the Micra AV group had significantly lower rates of complications (adjusted HR, 0.50; 95% CI, 0.43 to 0.57; p<.0001), lower reinterventions (adjusted HR, 0.46; 95% CI, 0.36 to 0.58; p<.0001), and higher all-cause mortality (adjusted HR, 1.69; 95% CI, 1.57 to 1.83; p<.0001) compared to the dual chamber transvenous group. The authors concluded that leadless pacemakers with AV synchronous pacing demonstrated safety and efficacy. The authors noted limitations to the study. First, Medicare claims data was used, which is a secondary database without traditional clinical adjudication. Second, the comparator cohort included all individuals regardless of pacing indications, because it could not be reliably determined from the data.
Maclean et al conducted a retrospective study of data from the MAUDE database for events related to Micra tine fracture and damage (Maclean, 2024). Of the 4241 medical device reports, these included 2104 Micra VR and 2167 Micra AV reports. After duplicates were excluded, there were 230 reports including terms "fracture" and "tine." There were 7 reports of tine fracture and 19 reports of tine damage. Clinical signs and symptoms were reported in 2 of the 7 (29%) tine fracture cases and 4 of 19 (21%) of the tine damage cases. The authors concluded there is a low frequency of tine fracture and tine damage reports with the tine-based fixation mechanism of the Micra leadless pacing system.
Multiple studies have analyzed data from the International Leadless Pacemaker Registry (i-LEAPER), a European, multicenter, open-label, independent, and physician-initiated observational registry of the Micra leadless pacemaker devices. Mitacchione et al used i-LEAPER data to investigate outcomes of leadless pacemaker implantation following transvenous lead extraction at a median follow-up of 33 months (Mitacchione, 2023). The study cohort (N=1179) was grouped by those with leadless pacemaker implantation after transvenous lead extraction (TLE) (n=184) or de novo (n=995). There was no difference in leadless pacemaker-related major complications between TLE (1.6%) and de novo (2.2%) (p=.785) or all-cause mortality between TLE (5.4%) and de novo (7.8%) (p=.288). Pacing threshold was higher in the TLE group compared to the de novo group at implantation and follow-up. The authors noted that when the leadless pacemaker was deployed at a different right ventricular location than were the previous transvenous right ventricular lead was extracted, there was a lower proportion of individuals with high pacing threshold at implantation through 12-months follow-up. In another study by Mitacchione et al using the i-LEAPER database, they assessed sex differences in leadless pacemaker implantation (Mitacchione, 2023). The authors noted that of the overall population (N=1179), 64.3% were male. At median follow-up (25 months), female sex was not associated with leadless pacemaker-related major complications (HR, 2.03; 95% CI, 0.70 to 5.84; p=.190) or all-cause mortality (HR, 0.98; 95% CI, 0.40 to 2.42; p=.960). The authors conclude that females underrepresented in the study but had comparable safety and efficacy outcomes to males.
Lenormand et al conducted a retrospective observational study on the efficacy and safety of leadless cardiac pacing (Lenormand, 2023). Individuals (N=400) implanted with Micra VR (n=328) and Micra AV (n=72) were included in the analysis. The pacing threshold was similar between groups and remained stable through follow-up. There was no difference between median chronic pacing threshold between Micra VR (0.5 V) and Micra AV (0.5 V) (p=.87). In the overall population there were 14 individuals (3.5%) with major perioperative complications, 93% of which were in the Micra VR group. There were 116 deaths (29%) during follow-up, with mortality rates of 18% and 55% at 1 and 5 years, respectively. Pacemaker syndrome occurred in 6 (1.8%) individuals in the Micra VR group and no cases in the Micra AV group (p=.60). Pacing-induced cardiomyopathy occurred in 4 (1.2%) individuals in the Micra VR group and 2 (2.8%) individuals in the Micra AV group (p=.30). Overall, the authors conclude leadless pacing is safe. However, this study is limited as a retrospective observational study, and it did not have a comparison conventional transvenous cardiac pacing group.
Strik et al evaluated the safety and efficacy of Micra VR in young adults between 18 and 40 years (N=35) in a multicenter, retrospective, observational study (Strik, 2023). The primary safety endpoint was freedom from system-related or procedure-related major complications at 6 months. All patients met the primary safety endpoint at 6 months. During follow-up (26 ± 15 months), there were 3 deaths. The authors note these were not related to device implantation or malfunction. The authors conclude the results demonstrated favorable safety for the Micra VR. However, this study is limited by its small sample size and retrospective design.
Shah et al conducted a retrospective study reporting results from the Pediatric and Congenital Electrophysiology Society (PACES) Transcatheter Leadless Pacemakers (TLP) registry (Shah, 2023). Individuals (N=63) were 21 years of age or younger and met a class I or II indication for pacemaker implantation for a Micra device. Implantation was successful in 62 (98%) of the participants. During the follow-up period (mean, 9.5 ± 5.3 months), there were 10 (16%) complications including 1 cardiac perforation/pericardial effusion, 1 nonocclusive femoral venous thrombus, and 1 retrieval and replacement of TLP due to high thresholds. There were no deaths or device-related infections reported during the study period.
Ando et al studied the safety and performance of the Micra VR in the Micra Acute Performance (MAP) Japan cohort (N=300) (Ando, 2023). Within 30 days of implantation, there were 11 major complications in 10 individuals (3.33%; 95% CI, 1.61 to 6.04). These included 3 cardiac effusions/perforations, 2 events at the groin puncture site, 2 cases of deep vein thrombosis, and 4 pacing issues leading to system modifications. There were 2 deaths within 30 days of implantation, and a total of 22 deaths during the 12-month study period. The author conclude the safety and performance observed in this cohort was comparable to other global Micra trials.
Racine et al conducted a single center, retrospective study of individuals implanted with a Micra only (n=72) or a Micra and concomitant or delayed AVNA (n=12) (Racine, 2023). Two patients in the Micra with AVNA group had acute pacing threshold, requiring device retrieval. This was a single center study with a small sample size, so further evidence is needed to investigate the safety of implantation of Micra with AVNA.
Two retrospective studies have investigated implantation of Micra devices after cardiac surgery and valve interventions. Kassab et al studied individuals (N=9) who underwent Micra AV implantation within 30 days post-transcatheter aortic valve replacement (Kassab, 2024). There were no procedural complications and at follow-up (mean, 353 days) capture threshold and lead impedance remained stable. Huang et al studied individuals (N=78) who received Micra VR (n=40) or Micra AV (n=38) implants who had undergone cardiac surgery (n=50) or transcatheter structural valve interventions (n=28) (Huang, 2023). During 1-year follow up, there was 1 (1.3%) femoral access site hematoma requiring evacuation. Within 30 days, 4 (5.1%) patients were rehospitalized and 3 (3.8%) patients died. More evidence is needed to determine the safety of leadless pacemaker implantation after cardiac surgery and valve interventions. The authors of both papers noted several clinical characteristics and age contributed to the decision to implant leadless pacemakers instead of transvenous pacemakers. However, it is unclear whether these individuals were considered medically eligible for a conventional transvenous pacemaker.
Garweg et al conducted a real-world assessment of AV synchrony in leadless pacemakers (Garweg, 2023). They first conducted a retrospective analysis of participants from the MARVEL 2 study with persistent third degree AV block and normal sinus rhythm (n=40). The median atrial mechanical sensed-ventricular pacing (%AM-VP) was 79.1%, with a range of 21.6% to 95.0%, and was highly correlated with AVS measured from surface electrocardiogram (R² = 0.764, p<.001). The authors also conducted a large real-world analysis of individuals with Micra AV implants enrolled in the CareLink database with devices programmed to VDD mode (n=4384). They found that ventricular pacing exceeded 90% in 37.9% (n=1662) of these participants and was near 100% in 15.7% (n=689) of these participants. Overall, the authors concluded the results demonstrated stable AVS over time.
Lenormand et al conducted a retrospective study comparing the Micra VR and AV devices in individuals with sinus rhythm and complete atrioventricular block (N=93) (Lenormand, 2023). Between the VR (n=45) and AV (n=48) groups mean ventricular pacing burden was comparable (77% vs. 82%; p=.38), and there were more cases of pacemaker syndrome in the VR compared to AV group (5 patients vs. 0 patients; p=.02). Atrioventricular synchrony was assessed in the AV group. Median total AVS was 79% and there was poor A4 sensing in 7 (15%) of patients. The authors conclude that the Micra AV was able to provide AVS in most patients and was associated with no cases of pacemaker syndrome. However, this study is limited by its retrospective design and small sample size. More evidence is needed to compare the effectiveness and safety of the Micra VR and AV devices.
Santobuono et al presented a case report of a Micra AV with a sudden battery malfunction, which resulted in successful extraction and replacement with a new device in the right ventricle (Santobuone, 2024). The authors noted, to their knowledge, this is the first case of a sudden battery failure not related to elevated pacing threshold.
Garg et al analyzed data from the FDA MAUDE database to capture adverse events associated with the Aveir VR device (Garg, 2023). The database was queried on January 20, 2023 and there were a total of 98 medical device reports for the Aveir VR. They excluded duplicate, programmer-related, and introducer-sheath-related entries (n=34), so 64 entries were included in the final analysis. The most common reported events were high threshold/noncapture (28.1%, n=18), stretched helix (17.2%, n=11), device dislodgement (15.6%, n=10), and device separation failure (14.1%, n=9). Other reported events included high impedance (14.1%, n=9), sensing issues (12.5%, n=8), bent/broken helix (7.8%, n=5), premature separation (4.7%, n=3), interrogation problem (3.1%, n=2), low impedance (3.1%, n=2), premature battery depletion (1.6%, n=1), and inadvertent magnetic resonance imaging mode switch (1.6%, n=1). There were 10 miscellaneous events (15.6%). There were 8 serious patient injury events, including pericardial effusion requiring pericardiocentesis (7.8%, n=5) due to cardiac perforation, resulting in 2 deaths (3.1%), and sustained ventricular arrhythmias (4.6%, n=3). Overall, this study demonstrated that serious adverse events occurred, including life-threatening ventricular arrhythmias, pericardial effusion, device explantation/reimplantation, and death.
Tam et al conducted a non-randomized retrospective analysis of pacing threshold performance on the Aveir VR (n=123) compared to the Micra VR (n=139) (Tam, 2024). The primary endpoint was pacing threshold at various time points before, during, and through 3 months after the procedure. High pacing threshold was defined as ≥1.5 V at 0.4 ms for the Aveir VR and ≥1.5 V at 0.24 ms for the Micra VR. At the end of the procedure, more individuals in the Aveir VR group had a high pacing threshold (11.5%) compared to in the Micra VR group (2.2%) (p=.004). At 3 months, there was no difference in the probability of a high pacing threshold between the Aveir VR group (2.3%) and the Micra VR group (3.1%) (p=1.000). The authors note the Aveir VR demonstrated satisfactory performance, however the study was limited by its small sample size and lack of randomization.
The Aveir Leadless Pacemaker pivotal trial was a prospective, multicenter, single-group study enrolling 300 individuals to evaluate the safety and performance of the dual-chamber leadless pacemaker system (Knops, 2023). Inclusion criteria for the study population included having at least 1 clinical indication for device implant based on evidence-based dual chamber pacing guidelines and at least 18 years of age. Results through 3 months post implantation were reported. The primary safety endpoint was freedom from complications and the primary performance endpoint was a combination of adequate atrial capture threshold and sensing amplitude at 3 months. Within 90 days post implantation, there were 35 complications in 29 individuals, of which 28 complications occurred within 2 days post implantation. There were 271 individuals (90.3%; 95% CI, 87.0% to 93.7%) free from complications. Adequate atrial capture threshold and sensing amplitude were met in 90.2% of patients (95% CI, 86.8% to 93.6%). There were 4 deaths reported during follow-up.
In 2012, The American College of Cardiology Foundation (ACCF), American Heart Association (AHA), and the Heart Rhythm Society (HRS) issued a focused update of the ACCF/AHA/HRS 2008 guidelines for device-based therapy of cardiac rhythm abnormalities (Epstein, 2013). These guidelines included recommendations regarding permanent pacemaker implantation in individuals with class I or II indications.
|
|
|
|
| CPT/HCPCS: | |
|
|
|
| References: |
American Heart Association(2016) Statement of the American Heart Association to the Food and Drug Administration Circulatory System Devices Panel February 18, 2016. https://www.fda.gov/downloads/AdvisoryCommittees/CommitteesMeetingMaterials/MedicalDevices/MedicalDevicesAdvisoryCommittee/CirculatorySystemDevicesPanel/UCM486235.pdf. Accessed August 6, 2018. Centers for Medicare & Medicaid Services.(2017) Decision Memo for Leadless Pacemakers (CAG-00448N). 2017; https://www.cms.gov/medicare-coverage-database/details/nca-decision-memo.aspx?NCAId=285&bc=ACAAAAAAQAAA&. Accessed August 31, 2018. Chinitz LA, El-Chami MF, Sagi V, et al.(2023) Ambulatory atrioventricular synchronous pacing over time using a leadless ventricular pacemaker: Primary results from the AccelAV study. Heart Rhythm. Jan 2023; 20(1): 46-54. PMID 36075532 Cohen M, Bush D, VetterV, et al.(2001) Permanent epicardial pacing in pediatric patients: seventeen years of experience and 1200 outpatient visits. Circulation. 2001 May 29;103(21):2585-90. Crossley GH, Piccini JP, Longacre C, et al.(2023) Leadless versus transvenous single-chamber ventricular pacemakers: 3 year follow-up of the Micra CED study. J Cardiovasc Electrophysiol. Apr 2023; 34(4): 1015-1023. PMID 36807378 Duray GZ, Ritter P, El-Chami M, et al.(2017) Long-term performance of a transcatheter pacing system: 12-Month results from the Micra Transcatheter Pacing Study. Heart Rhythm. May 2017;14(5):702-709. PMID 28192207 Epstein AE, DiMarco JP, Ellenbogen KA, et al.(2012) 2012 ACCF/AHA/HRS focused update incorporated into the ACCF/AHA/HRS 2008 guidelines for device-based therapy of cardiac rhythm abnormalities: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines and the Heart Rhythm Society. J Am Coll Cardiol. Jan 22 2013;61(3):e6-75. PMID 23265327 FDA Presentation(2018) Circulatory System Devices Panel Meeting: Leadless Pacemakers. https://www.fda.gov/downloads/AdvisoryCommittees/CommitteesMeetingMaterials/MedicalDevices/MedicalDevicesAdvisoryCommittee/CirculatorySystemDevicesPanel/UCM486733.pdf. Accessed August 6, 2018. Fernández AL, García-Bengochea JB, Ledo R, et al.(2004) Minimally invasive surgical implantation of left ventricular epicardial leads for ventricular resynchronization using video-assisted thoracoscopy. Rev Esp Cardiol. 2004 Apr;57(4):313-9. Food and Drug Administration.(2016) FDA Executive Summary Memorandum General General Issues: Leadless Pacemaker Devices Prepared for the February 18, 2016 meeting of the Circulatory System Devices Advisory Panel Gaithersburg Hilton; Gaithersburg, MD. https://www.fda.gov/downloads/AdvisoryCommittees/CommitteesMeetingMaterials/MedicalDevices/MedicalDevicesAdvisoryCommittee/CirculatorySystemDevicesPanel/UCM485093.pdf. Accessed August 6, 2018. Food and Drug Administration.(2018) Summary of Safety and Effectiveness Data (SSED): Micra® Transcatheter Pacing System. https://www.accessdata.fda.gov/cdrh_docs/pdf15/P150033B.pdf. Accessed August 6, 2018. Gillis AM, Russo AM, Ellenbogen KA, et al.(2012) HRS/ACCF expert consensus statement on pacemaker device and mode selection. J Am Coll Cardiol. Aug 14 2012;60(7):682-703. PMID 22854177 Healey JS, Toff WD, Lamas GA, et al.(2006) Cardiovascular outcomes with atrial-based pacing compared with ventricular pacing: meta-analysis of randomized trials, using individual patient data. Circulation. Jul 4 2006;114(1):11-17. PMID 16801463 Kempa M, Laskawski G, Budrejko S, et al.(2019) Implantation of a dual-chamber pacemaker with epicardial leads in adults using a minimally invasive subxyphoid approach. Pacing Clin Electrophysiol. 2019 May;42(5):537-541. doi: 10.1111/pace.13651. Epub 2019 Mar 18. Kirkfeldt RE, Johansen JB, Nohr EA, et al.(2011) Risk factors for lead complications in cardiac pacing: a population-based cohort study of 28,860 Danish patients. Heart Rhythm. Oct 2011;8(10):1622-1628. PMID 21699827 Kirkfeldt RE, Johansen JB, Nohr EA, et al.(2014) Complications after cardiac implantable electronic device implantations: an analysis of a complete, nationwide cohort in Denmark. Eur Heart J. May 2014;35(18):1186-1194. PMID 24347317 Knops RE, Tjong FV, Neuzil P, et al.(2015) Chronic performance of a leadless cardiac pacemaker: 1-year follow-up of the LEADLESS trial. J Am Coll Cardiol. Apr 21 2015;65(15):1497-1504. PMID 25881930 Kubus p, Materna o, Gebauer,R, et al.(2012) Permanent epicardial pacing in children: long-term results and factors modifying outcome. Europace. 2012 Apr;14(4):509-14. doi: 10.1093/europace/eur327. Epub 2011 Oct 11. Lakkireddy D, Knops R, Atwater B, et al.(2017) A worldwide experience of the management of battery failures and chronic device retrieval of the Nanostim leadless pacemaker. Heart Rhythm. Dec 2017;14(12):1756-1763. PMID 28705736 Lau KC, William-Gaynor j, Fuller SM, et al.(2015) Long-term atrial and ventricular epicardial pacemaker lead survival after cardiac operations in pediatric patients with congenital heart disease. Heart Rhythm. 2015 Mar;12(3):566-573. doi: 10.1016/j.hrthm.2014.12.001. Epub 2014 Dec 4. Lloyd M, Reynolds D, Sheldon T, et al.(2017) Rate adaptive pacing in an intracardiac pacemaker. Heart Rhythm. Feb 2017;14(2):200-205. PMID 27871854 Micra Physician Brochure. http://www.medtronic.com/content/dam/medtronic-com/01_crhf/brady/pdfs/medtronic-micra-transcatheter-pacing-system-hcp-brochure.pdf. Accessed August 6, 2018. Mikhael F. El-Chami M, et.al.(2018) Leadless Pacemaker Implant in Patients with Pre-Existing Infections:Results from the Micra Post-Approval Registry. Paper presented at: Heart Rhythm Scientific Sessions (May 10, 2018)2018; Boston, Massachusetts. Reddy VY, Exner DV, Cantillon DJ, et al.(2015) Percutaneous Implantation of an Entirely Intracardiac Leadless Pacemaker. N Engl J Med. Sep 17 2015;373(12):1125-1135. PMID 26321198 Reddy VY, Exner DV, Doshi R, et al.(2022) Primary Results on Safety and Efficacy From the LEADLESS II-Phase 2 Worldwide Clinical Trial. JACC Clin Electrophysiol. Jan 2022; 8(1): 115-117. PMID 34863657 Reddy VY, Exner DV, Doshi R, et al.(2023) 1-Year Outcomes of a Leadless Ventricular Pacemaker: The LEADLESS II (Phase 2) Trial. JACC Clin Electrophysiol. Mar 13 2023. PMID 36951813 Reddy VY, Knops RE, Sperzel J, et al.(2014) Permanent leadless cardiac pacing: results of the LEADLESS trial. Circulation. Apr 8 2014;129(14):1466-1471. PMID 24664277 Reddy VY, Miller MA, Knops RE, et al.(2016) Retrieval of the Leadless Cardiac Pacemaker: A Multicenter Experience. Circ Arrhythm Electrophysiol. Dec 2016;9(12). PMID 27932427 Reynolds D, Duray GZ, Omar R, et al.(2016) A Leadless Intracardiac Transcatheter Pacing System. N Engl J Med. Feb 11 2016;374(6):533-541. PMID 26551877 Ritter P, Duray GZ, Steinwender C, et al.(2015) Early performance of a miniaturized leadless cardiac pacemaker: the Micra Transcatheter Pacing Study. Eur Heart J. Oct 1 2015;36(37):2510-2519. PMID 26045305 Ritter P, Duray GZ, Zhang S, et al.(2015) The rationale and design of the Micra Transcatheter Pacing Study: safety and efficacy of a novel miniaturized pacemaker. Europace. May 2015;17(5):807-813. PMID 25855677 Roberts PR, Clementy N, Al Samadi F, et al.(2017) A leadless pacemaker in the real-world setting: The Micra Transcatheter Pacing System Post-Approval Registry. Heart Rhythm. Sep 2017;14(9):1375-1379. PMID 28502871 Sperzel J, Defaye P, Delnoy PP, et al.(2018) Primary safety results from the LEADLESS Observational Study. Europace. Sep 01 2018; 20(9): 1491-1497. PMID 29365073 Steinwender C, Khelae SK, Garweg C, et al.(2020) Atrioventricular Synchronous Pacing Using a Leadless Ventricular Pacemaker: Results From the MARVEL 2 Study. JACC Clin Electrophysiol. Jan 2020; 6(1): 94-106. PMID 31709982 Tjong FVY, Knops RE, Neuzil P, et al.(2018) Midterm Safety and Performance of a Leadless Cardiac Pacemaker: 3-Year Follow-up to the LEADLESS Trial (Nanostim Safety and Performance Trial for a Leadless Cardiac Pacemaker System). Circulation. Feb 6 2018;137(6):633-635. PMID 29431664 U.S. Food and Drug Administration (FDA).(2021) Letter to Health Care Providers. Leadless Pacing Systems: Risk of Major Complications Related to Cardiac Perforation During Implantation. November 17, 2021; https://www.fda.gov/medical-devices/letters-health-care-providers/leadless-pacing-systems-risk-major-complications-related-cardiac-perforation-during-implantation. Accessed April 7, 2022. U.S. Food and Drug Administration (FDA).(2022) Summary of Safety and Effectiveness Data: Aveir Leadless Pacemaker (P150035). March 31, 2022; Udo EO, Zuithoff NP, van Hemel NM, et al.(2012) Incidence and predictors of short- and long-term complications in pacemaker therapy: the FOLLOWPACE study. Heart Rhythm. May 2012;9(5):728-735. PMID 22182495 United States of America Department of Health and Human Services Food and Drug Administration(2016) Transcript of the United States of America Department of Health and Human Services Food and Drug Administration Center for Devices and Radiological Health Medical Devices Advisory Committee: Circulatory System Devices Panel Meeting February 18, 2016. https://www.fda.gov/downloads/AdvisoryCommittees/CommitteesMeetingMaterials/MedicalDevices/MedicalDevicesAdvisoryCommittee/CirculatorySystemDevicesPanel/UCM489547.pdf. Accessed August 6, 2018. Warner K, Halpin d, Berul C, et al.(1999) Placement of a Permanent Epicardial Pacemaker in Children Using a Subcostal Approach. Ann Thorac Surg 1999;68:173–5 Zuckerman B, Shein M, Paulsen J, et al.(2016) Circulatory System Devices Panel Meeting: Leadless Pacemakers. FDA Presentation.February 18, 2016; https://www.fda.gov/media/95985/download. Accessed April 8, 2022. |
|
|
|
|
Group specific policy will supersede this policy when applicable. This policy does not apply to the Wal-Mart Associates Group Health Plan participants or to the Tyson Group Health Plan participants.
CPT Codes Copyright © 2024 American Medical Association. |
|